Erebus - Level 5: Erebus Research

Erebus - Level 5: Erebus Research is the fifth level of Doom 3: Resurrection of Evil. This level is notable for its toxic waste tunnels which occupy the second part of the level. The player collects an enviro suit and then proceeds into a series of tunnels filled with toxic waste. Similar to the oxygen supply in outdoor atmospheres, the player has to periodically collect enviro tanks to refill their air supply. However, if the air supply runs out, the toxic environment will harm the player much more quickly than the outdoor atmosphere would if the oxygen were to run out there. Note that the entire tunnels are hazardous in this way, even the upper walkways; not just the toxic sludge itself. The enviro suit also limits the player's field of vision somewhat, but to compensate for this it has a flashlight attached to its helmet.

The maggots, cherubs, and mancubi return, and the player acquires the chaingun. This level also introduces the bio-suit zombie, much like a regular zombie but one that drops an enviro tank when killed.

In Doom 3: BFG Edition the enviro suit mechanic was removed from the game, and the player can go through the waste tunnels without a danger of running out of air; the player can also freely return to the armory from the toxic waste tunnels, which was not possible in the original game once the enviro suit was put on.

Summary
After fighting his way through some corridors, the marine reaches Dr. Cloud, who scans The Primitive and confirms that the Artifact is an ancient weapon of incredible power and that it serves as a gateway of sorts between our world and Hell. Dr. Cloud also gives the marine a key to the armory. The marine takes another road to the start of the level and proceeds through the armory, equipping himself with a chaingun along the way. Just after the armory, the marine finds the entrance to the waste tunnels. He equips an enviro suit and proceeds to blast his way through the tunnels, encountering many enemies along the way, including several mancubi. After emerging from the tunnels, the marine takes off the enviro suit and proceeds to the exit airlock.

Objectives

 * Armory
 * Gain access to the Armory.


 * Surface Access
 * Get the environment suit and follow the waste tunnels to the cargo station on the surface.

Areas

 * Transfer Bay
 * Erebus Cargo Storage
 * Erebus Storage Hallway
 * Elevator Bay
 * Research Access
 * Research Support
 * Research Sector 2
 * Upper Cargo Storage


 * Cargo Storage Stairwell
 * Erebus Cargo Storage
 * Armory
 * Waste Tunnels Access
 * Waste Tunnels
 * Airlock
 * Surface Access
 * Airlock Chamber

Characters

 * Dr. Elizabeth McNeil
 * Dr. Cloud

PDAs

 * Sean Gibson. Found in Cargo Storage Stairwell.
 * Leo Avery. Found in Armory.
 * Nathan Reynolds (X-Box version only)

Enemies
The enemy count on Nightmare is the same as on Veteran. There is no difference in monster count in BFG Edition.

Items
The only difference in the item count in BFG Edition is the removal of all enviro tank pickups (due to the removal of enviro suit mechanic from the level) and an addition of a single large med kit to the level.

There are two health stations on the level, each has 100 health in reserve.

Starting inventory
If the player starts the level via a console command, they will start with these items:

Trivia

 * This level is divided into two parts on the Xbox version of the game: Erebus: Erebus Research and Erebus: Waste Management.